1. Field of the Invention
The present invention relates generally to an electrical connection box to be mounted to an engine room of a motor vehicle.
2. Description of the Related Art
Various electric equipments are mounted to a motor vehicle as a moving body. In order to supply electric power to those electric equipments, an electrical connection box is mounted at suitable places in the vehicle between a power source and the electric equipments. Such electrical connection box is mounted with electric components such as a connector, a relay and a fuse.
The term an electrical connection box used herein is also referred to as a junction block, a fuse block or a relay box.
FIG. 6 is a perspective view of a conventional electrical connection box 101. FIG. 7 is a cross-sectional view of the conventional electrical connection box 101 taken along a line shown in FIG. 6. The conventional electrical connection box 101 includes a first cassette block 103, a second cassette block 105, a plurality of electric components (not shown) mounted to the respective cassette blocks 103, 105 such as a relay, a fusible link and a fuse, a plurality of bus bars 108, 109 as a connection member connected to the respective electric components, a connection structure 110 having a mechanical connection structure 110A connecting the cassette blocks 103, 105 to each other and an electrical connection structure 110B connecting the bus bars 108, 109 to each other, and a housing 102 receiving the cassette blocks 103, 105 connected to each other as well as the bus bars 108, 109 connected to each other.
The respective cassette blocks 103, 105 are formed into a block-like shape. As shown in FIG. 7, each of the cassette blocks 103, 105 is mounted with the plurality of electric components connected with the bus bars 108, 109.
The mechanical connection structure 110A includes an insert portion 104 provided to the first cassette block 103 and a receiving portion 106 provided to the second cassette block 105 and arranged to receive the insert portion 104.
The electrical connection structure 110B includes a male terminal 111 provided to the bus bar 109 and a female terminal 112 provided at the bus bar 108. The female terminal 112 includes a slit portion 108a for receiving the male terminal 111 (thus a front view of the female terminal 112 is in a turning-folk-like shape).
For the electrical connection box 101, when the cassette blocks 103, 105 are moved towards each other along an insertion direction Z, the insert portion 104 is inserted into the receiving portion 106 so that the cassette blocks 103, 105 are attached (mechanically connected) to each other. At the same time, the male terminal 111 is inserted into the slit portion 108a of the female terminal 112 so that the bus bar 108 attached to the first cassette block 103 and the bus bar 109 attached to the second cassette block 105 are electrically connected to each other (refer for example to Japanese Patent Application Publication No. 2006-345616).
However, there is a problem in the above-described conventional electrical connection box 101. That is, the conventional electrical connection box 101 requires the connection structure 110 having the mechanical connection structure 110A for connecting the cassette blocks 103, 105 to each other and the electrical connection structure 110B for connecting the bus bars 108, 109 to each other. Thus, the size of the conventional electrical connection box 101 (the housing 102) is increased to receive the connection structure 110.
There is another problem in the conventional electrical connection box 101. That is, the cassette blocks 103, 105 are attached to each other by inserting the insert portion 104 of the first cassette block 103 into the receiving portion 106 of the second cassette block 105. Also, the bus bars 108, 109 are connected to each other by inserting the male terminal 111 into the slit portion 108a of the female terminal 112. Thus, for example the vibratory motion of the moving vehicle may cause the cassette blocks 103, 105 to move away from each other along the insertion direction Z, causing the insert portion 104 to be separated from the receiving portion 106. As a result, the cassette blocks 103, 105 may be separated from each other as well as the bus bars 108, 109, thereby breaking the electrical connection between the bus bars 108, 109.